The leader of the main Greek opposition party, New Democracy (EPP), called on Wednesday (5 December) on Greek political parties to block the name change deal recently reached between Athens and Skopje after almost thirty years of dispute.

“New Democracy will vote against the Prespa agreement [the name change deal] and urges all parties to do the same when it comes for ratification in the Greek parliament,” Kyriakos Mitsotakis said, adding there was only one way to limit the “national damage” allegedly caused by the deal.

“This is the reasonable demand of the vast majority of Greek citizens,” Mitsotakis added.

He made his statement following press reports in Skopje that quoted Zoran Zaev, the prime minister of the former Yugoslav Republic of Macedonia (FYROM), as saying that with the Prespa Agreement, there will be a possibility that the “Macedonian” language, a South Slavic language related to Bulgarian, is taught in Greece.

“The statement confirms in the clearest way what New Democracy has been saying since the very first moment. The recognition of the so-called Macedonian language opens the Pandora’s box to revive all the historically groundless claims of Skopje,” the centre-right politician said.

On Tuesday Greek premier Alexis Tsipras issued a statement saying the agreement must be upheld so that FYROM can join the EU and NATO.

Fearing a derail of the process, Matthew Nimetz, the United Nations Special Representative for the name dispute, intervened and called on Skopje to stick to the agreement.

Several hours later, the government in Skopje said Zaev’s statements were misinterpreted and made clear that it had no intention to meddle with Greece’s domestic issues, such as language education.

After FYROM took a step back on the issue, the Greek government lashed out against New Democracy.

“Mr Mitsotakis must be serious and not play with critical national issues in his attempt to fish in the muddy waters of the nationalist audience,” the government said.

Last June, Prime Minister Zaev and his Greek counterpart Alexis Tsipras reached a breakthrough deal on a 25-year name dispute and agreed on the name North Macedonia.

The deal has been generally endorsed by the EPP but rejected by some of its members, including those from the two countries involved, meaning Greece’s New Democracy and FYROM’s VMRO-DPMNE.

Similarly, the Pan-Hellenic Socialist Movement (Pasok) also rejects the deal despite the wide endorsement of the EU socialist family.

The Socialists and Democrats group (S&D) continue to criticise the negative stance of center-right opposition parties in Athens and Skopje towards the landmark name deal but also turn a blind eye to their member party in Greece, which disapproves of it.

Speaking at the EPP congress on 8 November in Helsinki, Bulgaria’s Prime Minister Boyko Borissov criticised the EPP sister parties in Greece and Macedonia, but also the EPP leadership, for what he said was “lack of discipline”.

“What is happening? The Social-democrat party in Macedonia wants to join the EU and NATO, the Greek far-left wants its neighbour Macedonia to join the EU and NATO, but our sister parties in these countries don’t want it. I want to ask a simple question. Is there discipline in the EPP or not?” Borissov said.

Manfred Weber, the European People’s Party (EPP) Spitzenkandidat for the EU elections, has been silent over the name change deal reached this year between Athens and Skopje. The deal has been generally endorsed by the EPP but rejected by some of its members, including those from the two countries involved.